Question

A compound has a molar mass of 200g. What is its molecular formula if it contains 48.0% C, 8.0% H, 28.8% N, and 16.0% O?

Answer 1

  C             H            N          O

48/12        8/1       28.8/14   16/16    -first you divide the given amount with the atomic mass

4                8          2.057         1     -then divide the answers you get by the smallest answer which in this case is 1

4/1           8/1           2.057/1        1/1

4      :         8      :        2.057    :    1     -this is now your ratio, now the next step is to check whether or not any of your answers includes a decimal, if it doesn't then move on to the next step, if it does, then multiply the whole thing by 2

(4  :  8  :  2.057  :  1) x 2 =    8  :  16  :  4  :  2

this is your final ratio --> 8  :  16  :  4  :  2  , now what you do is, write the empirical formula, which is = C8H16N4O2  

now all you have to do find out the Mr of the compound

-->  (12 x 8) + (1 x 16) + (14 x 4) + (16 x 2) = 200

now you divide the molar mass given and the Mr

= 200/200

= 1

Answer 2

Answer:

$C_{8}H_{16}N_{4}O_{2}$

Explanation: